Vacuum heating system



Aug. 4, 1925. 1,548,224

- ,w. "r. THOMSEN VACUUM HEATING SYSTEM Filed Mapch 31, 1924 IN VEN T02 My/l flm 7: 71007560- vacuum pumpwhich is also used to remove lowing is a full, clear, and

- tems now ingeneral use Patented Aug. 4, 1925.

WILLIAM 'r. TVI-IOMSEN, on ST. Louis, MISSOURI.

.VAGUUM HEATING SYSTEM.

Application filed March 31, 1924. Serial No. 703,148.

To all whom it may I Be it known that 1, WILLIAM T. THOM- snn, a citizen of the United States, residing at St. Louis, Missouri, have invented a certain new and useful Improvement in Vacuum'Heating Systems, of which the folexact description, such as will enable others skilled in the art to which it appertains to make and use the same. I v

This invention relates to vacuum heating systems. H

lnthe conventional vacuum heating sys the water of condensation that collects in the radiators and return lines is pumped back to the boiler byfa concern: 3

air from the radiators and return lines and create a vacuum in thereturn lines. Each radiator is equipped with a thermostatic orother type of trap'that permits the water ot' condensation to escape from the radiator through the return line, but which prevents the steam suppliedto theradiator from escaping from same through the return line. In the normal operation of the system the vaccum pump starts and stops automatically according to the vacuum that, exists in v the return line leading back to the pump,

the pump being governed by a controlling the pump to start when the vacuum drops below a certain degree, and which causes the pump to stop and remain inoperative after the vacuum has been restored to normal. When the radiators are filled with steam maintained in an inoperative condition by the vacuum which then exists in the return lines. When one or more of the radiators start to cool off the water of condensation that collects in the radiators escapes from the same into the return lines, and after a certain quantity of water of condensation has collected in-the return systemythe weight or pressure eXertedby; said" water I on the controlling device of the pump causes the pump to become operative, whereupon the Water of condensation will be pumpedback to the boiler. The above cycle continues so long, as sufficient steam is being generated in the boiler to keep steam, but it, the pressure in the boiler drops to such a point that suflicient ste'amis'not being generated .to keep the radiators filled with steam, then. the thermostatic traps on the radiators cool off, due to therapid cone device which causes munication is established ators,

the vacuum pump will be the radiators .full of densationtaking place in the radiators, and assume such acondition that direct combetween the India tors and the returntlines. The rapid condensation taking place in the radiators creates awhigh vacuum in the radiators which is exerted on the boiler and on the return lines that lead from the radiators. The Vapor forming in the boiler is drawn into the radiators by this high vacuum, and as soon as said vapor condenses in the radithe water of condensation escapes from same throughthereturn' lines, but in view of thefact that the radiators are then in direct. communication with the return static traps, the h gh vacuum that exists in the radiators is exerted'onthe water. of

condensation in the return line in such way asto prevent said water fromexerting sufiicient Weightv or pressure on the controlling device of the pump to cause the pump to become operative, even though an abnormally large quantity of'water of condensation has collected in the return pipe of the system. I 7

Under such a condition the supply of waterfinthe boilerrapidly becomes diminished, and if the condition is allowed to continue for a considerable period, the boiler is liable to break, due to an insuflicient supply of water. Accordingly, in the conventional vacuum heating systems itis necessary to carefully watch the fire in the boiler,

in order to maintain suflicient pressure on e to an abnormal vacuum heating systems, I

a device ico-mnionly termed 'a. vac'uumbreaker is,v sometimes installedin the return line leading to the boiler so as to automatically admit sufiicient air tothe return line to prevent an abnormally highvacuum from being created in the return'line when the boiler isnot generating sufficient steam to, keep: the radiators filled with steam, or, in other words, on the radiators are in such a condition that the high vacuum created in the radiators by when the thermostatic traps the condensation of vapor drawn from the boiler is exerted on the return line. The air that is admitted to the return line by the vacuum breaker effectively destroys a high vacuum in the return line and permits the water of condensation in the return line to exert sufiicient weight or pressure on the controlling device of the vacuum pump to cause said pump to become operative after a certain quantity of water of condensation has collected in the return line, but the use of a vacuum breaker is objectionable, because it admits air to the system, thus necessitating the expenditure of considerable power to expel said air, because the eh'iciency of a vacuum heating system is dependent upon the absence of air in the circulating system.

One object of my invention is to provide a sealed vacuum heating system which is constructed in such a manner that it is not necessary to admit air to the return line leading to the boiler or carefully watch the fire in moderate weather and keep a certain pressure on the boiler, in order to eliminate the possibility of the boiler bursting, due to an abnormal drop in the level of the water in the'boiler, thereby effecting a con siderable saving in the quantity of fuel used to operate the system in moderate weather and insuring a highly efficient heating system, due to the absence of an abnormal quantity of air in the circulating system.

Another object is to provide a vacuum heating system which is completely sealed to the atmosphere and constructed in such a manner that the vacuum pump can remain inactive for longer periods than in the conventional vacuum heating systems without reducing the efiiciency of the system, thereby effecting a considerable saving in the power used to operate the pump.

Another object is to provide a steam heating system that will function like a conventional'vacuum heating system in extremely cold weather, like a vapor system in moderately cold Weather, and like a vapor vacuum system in mild weather, the system being constructed in such a way that vapor will be supplied to the radiators at low temperatures, such as 170 to 190, and the water of condensation returned to the boiler while the vacuum pump is inoperative.

Another object is to provide a vacuum heating system which is constructed in such a way that the amount of vapor in each radiator can be accurately controlled, there by reducing the quantity of fuel required to operate the system in moderate weather.

And still another object is to provide a vacuum heating system which is so constructed that the Water of condensation will be returned automatically to the boiler, regardless of the conditions existing in the system, even when the vacuum pump is in operative, thereby insuring a safe water line in the boiler at all times. Other objects and desirable features of my invention will be hereinafter pointed out.

To this end I have devised a sealed vacuum heating system which is constructed in such a way that the return line leading from the radiators is connected with a boiler in such a manner that a high vacuum created in the radiators by rapid condensation of vapor therein, when the radiators are not completely filled with steam, will be exerted uniformly or equally on the steam supply line leading from the boiler to the radiators and on the return line leading from the radiators to the boiler, thereby permitting the Water of condensation to return freely by gravity to the boiler, even though the vacuum pump is maintained in an inoperative condition by the vacuum which then exists in the return line. I accomplish this highly desirable result by connecting the radieting devices with the boiler so as to produce a sealed system that is cut off from the atmosphere, arranging a bypass in the re turn line around the vacuum pump and providing said bypass with a check valve that opens towards the boiler, thereby producing a vacuum heating system in which the water intake to the boiler is connected with the return line leading from the radiators, in such a manner that a pull exerted on the boiler in a direction tending to draw vapor from same into the radiators is also exerted on the return line ina direction tending to draw Water of condensation from same into the boiler.

Figure l of the drawings is a perspectivevieW illustrating my improved vacuum heating system; and p Figure 2 is a detail view of the by-pass around the vacuum pump that forms a direct connection between the water intake to the boiler and the return line leading to the vacuum pump from the radiators of the system.

Referring to the drawings, A designates a boiler of any preferred type or construction, B designates one of the radiators of the system, 1 designates the steam supply line leading from the boiler to the radiator through which steam is supplied to the radiator, 2 designates the return line leading from the radiator throughwhich the water ofcondensation escapes therefrom, l designates a manually-operable valve in the. steam supply line that is adapted to be adjusted to regulate the supply of steam or vapor to the radiator, C designates an automatic trap, preferably, a thermostatic trap, that governs the escape of the air and water of condensation from the radiator into the return line 2, D designates a Vacuum pump" operated by an electric motor E or other suitable source of power and combined with that leads from the pump the controlling device the return line 2 'inlsuch afmanner thatit will discharge the air and water of condensation from the return line 2 and create a vacuum in said return line, the water and air that enter the pump D being separated therein and the water thereafter discharged into the boiler A through a water intake 3 D. The pump D is started and stopped automatically by a controlling device E that is governed by the vacuum existing in the return line 2, said controlling device E. being connected with the return line by means of a pipe 4. I have not illustrated the construction of E, as said device may be of the type or kind now generally used 'in vacuum heating systems, the conventional vacuum pump controlling .device comprising a diaphragm that is moved in one direction and maintained in a certain position by the vacuum that exists in the return line 2 and moved in the opposite direction by the weight or pressure exerted on same by water of condensation that collects in the return line2 and rises in the pipe l. In the normal operation of the system, when sufficient steam is'being generated in the boiler to keep the radiators filled with steam," the vacuum'pump D is maintained at rest by the vacuum. created in the return line 2 by the previous operation of said pump. The condensation of the steam in the radiator B causes water to collect in the return'line 2, and after a certain'quantity of water of condensation has collected in said return line, the reduced sufficiently to permit the diaphragm of the'controlling device E to flex, due to the weight or pressure of the water of condensation on same, and thus cause the vacuum pump D to become operative. As soon as said pump cuts into service, the water of condensation that has collected in the return line 2 and any air that has entered said line, are pumped out of same into the separating chamber of the pump D, thereby causing the normal vacuum to be re-established in the return line and the water removed from the line 2 to hereturned to the boiler. The pump D becomes inoperative as soon asthe normal vacuum has been re-establishe If the pressure on the boiler A drops to such a point'that sufficient steam is not being generated to keep the radiator B filled with steam, the thermostatic trap C cools off and assumes-such a; condition that the return line 2 isin direct communication with the radiator B. The rapid rate of condensationwhich then takes place in the radiator. creates a high vacuum therein, which high vacuum, in the conventional vacuum heating. system, virtually holds the water of condensation in the return line '2 in suspension and prevents said water from vacuum therein is acting onthe controlling device E of the pump ,in such a way as to cause said pump to becomeoperative. In my improved system, however, the created in the radiator B by the rapid condensation of steam or vapor therein, when said radiator is not completely filled with steam, has no. effect on water of condensation to the boiler, owing to the fact that a icy-pass or vacuumequah izer pipe F is arranged in the return line 2 leading from the radiators to theboiler in such a way that-it forms a direct cross connection between said'return line 2 and the water intake 3 of the boiler A ahead of the discharge valve of the pump D, the water of condensation in the return line 2 being capable of passing 1y into the boiler through the bypass F. As shown in Figure 2, theby-pass F is pro vided with acheck valve 5 that opens towards the boiler A, so as to prevent the water-in the boiler being sucked out of same through theintake 3 and by-pass F when thevacuum pump D is in operation. With avacuum heating system of the construction above described the bypass F is alwaysm a densation to passfreely from the return pipe 2Ito,the boiler when vapor is being drawn from the boiler by a high vacuum existing in the radiators, I Accordingly, the system is absolutely automatic, as the by pass F and pump D are always in readiness to perform their respective functions and neither one affects the other. :ThatLis to say, in my improved system the vacuum high vacuum that is the return of the freely from same direct condition to permit water of con pump D starts and stops automatically so 1' as'to discharge water of condensation and air from the return system when the boiler is generating sufficient steam to keep the radiators filled with team, without liability of drawing water out of the boilermit water in the around the pump D and enter the water intake of the boiler A when a high vacuum radiators, due to the rapid condensation of c the vapor that is is established in the drawn into the radiators from the boiler. The result'is that the vacuum pump D- remains inactive when the pressure on the boiler is low, but this low pressure has no tendency to cause the water level of the boiler to drop abnormally, due to the fact.

F equalizes the vacuum on the boiler, and thus permits the water of condensation in the return pipe 2 to flow back to the boiler.

From the foregoing it will be seen that that. the by-pass my invention eliminates the possibility of the boiler bursting, due to diminution of the water in the boiler when the steam pressure is low, and it produces a steam heating system that will function like a conventional vacuum heating system in extremely cold weather, function like a vapor system in moderately cold weather and function like a vapor vacuum heating system in mild weather, the change from one type to the other being automatic.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

l. A vacuum steam heating system, comprising a boiler, radiating devices combined with said boiler so as to produce a sealed system that is cut off from the atmosphere, a return line leading from said radiating devices back to the boiler, an automatic vacuum pump for removing Water of condensation and air from the return line and for feeding said water back to the boiler, and means whereby the water of condensation in the return line can flow back to the boiler in the event the vacuum pump remains inoperative at a time when the return line is under an abnormally high vacuum.

2. A vacuum steam heating system, comprising a boiler, radiating devices combined with said boiler so as to produce a sealed system that is cut off from the atmosphere, a return line leading from said radiating devices back to the boiler, an automatic vacuum pump for removing water of condensation and air from the return line and for feeding said water back to the boiler, and

means whereby a vacuum exerted on the boiler in a manner tending to draw vapor from same into the radiating devices of the system causes the water of condensation that has collected in the return line to be conducted back to the boiler, even though the vacuum pump is at rest.

3. A vacuum steam heating system, comprising a boiler, radiating devices combined with said bolier so as to produce a sealed system that is cut off from the atmosphere, a return line leading from said radiating devices back to the boiler an automatic vacuum pump for removing water of condensation and air from the return line and for feeding said water back to the boiler, and a by-pass in the return line extending around said pump and provided with a check valve that opens towards the boiler.

4. In a vacuum steam heating system, a boiler, radiating devices combined with said boiler so as to produce a sealed system that is cut off from the atmosphere, a return line leading from said radiating de vices back to the boiler, an automatic vacuum pump arranged in said return line, a thermostatic trap associated with each radiating device for governing the discharge of air and water of condensation from same into said return line, an equalizing pipe connected at one end to said return line at a point beyond the intake or" the pump and connected at its opposite end to said return line at a point beyond the discharge of the pump, and a check valve in said equalizing pipe that opens towards the boiler.

WILLIAM T. THOMSEN. 

